print(4 and 5)			--> 5
print(nil and 13)		--> nil
print(false and 13)		--> false
print(4 or 5)			--> 4
print(false or 5)		--> 5
print(not nil)			--> true
print(not false)		--> true
print(not 0)			--> false
print(not not nil)		--> false